Figure 10.

Model showing the proposed physiological role of mitochondrial CAH4/5 in the CCM of Chlamydomonas. In (A) known CAs (CAH1, CAH2, CAH3, and LCIB) are indicated in the periplasmic space, the chloroplast stroma, and the thylakoid lumen, respectively. Dotted lines indicate the leakage of CO₂ from the pyrenoid and how it is recaptured by different layers of CAs. PGA, phosphoglyceric acid. B, The proposed recapturing of CO₂ in mitochondria. The CO₂ leakage arises from the chloroplast, mitochondrial respiration, and photorespiration.